Security increased as parliament returns without MP Helen Haines

The prime minister will pass a motion to suspend normal business in parliament today, allowing MPs to share a message of support for Indi MP Helen Haines.

Ms Haines is in a serious but stable condition in hospital after being hit by a car in what police are treating as a deliberate attack.

Security at Parliament House has been increased, as police warn there is a direct correlation between inflammatory political discourse and threats against politicians.

Parliament returns today with one of its most respected members missing, as MPs reconvene in Canberra without Helen Haines.

Security has been strengthened at Parliament House after a car struck the independent MP outside her Wangaratta electorate office in what police are treating as a deliberate attack.

The 65-year-old mother of three, admired across the political divide for her integrity, has had both legs amputated after suffering severe injuries to her lower body.

Prime Minister Anthony Albanese is expected to move a motion in the House of Representatives that would set aside much of the day for MPs to offer messages of support.

Ms Haines's seat will be empty at Question Time, with fellow crossbenchers pledging to carry forward her leadership example as parliament grapples with ways to approach security in their respective communities.

"The people of Indi will be represented by an empty seat this week, but I hope their voices and the voices of all Australians who want the kind of democracy Helen represents will be heard clearly by the parliament," independent MP Kate Chaney said.

Kooyong MP Monique Ryan said those who loved Ms Haines would try to do justice to the parliament's "most gentle, principled, and kind member".

"I hope that all members will rise to the occasion as Helen would do were she with us," she said.

Independent Senator David Pocock said it was hard to articulate the "anguish" felt by his team and the wider community.

"We've been checking in with her family, her team and thinking about how we can best support Helen and everyone most impacted by these events now and over the long term," he said.

"Helen's impact will continue to be felt, however, and should inspire us to keep working to improve our democracy."

In a letter sent to MPs on Friday, Speaker of the House Milton Dick and Senate President Sue Lions said there would be additional security across certain areas of Parliament House.

"The events of this week involving Dr Helen Haines MP have deeply affected the parliamentary community," they wrote.

"We also recognise that these events may understandably cause parliamentarians, their staff, and families to reflect on their safety and security, including whilst at Australian Parliament House."

MPs met with the AFP for a security briefing last week, with some reporting mixed experiences accessing support.

At the same time, a number of parliamentarians have stressed that safety must be balanced against the need to remain accessible to the communities they serve.

"The very nature of the jobs we do is we're interacting with people all the time as we should be," Labor frontbencher Catherine King said.

On Sunday, Australian Federal Police Commissioner Krissy Barrett said MPs had a critical role to play in their own safety, warning there was a direct correlation between moments of inflammatory political discourse and increased threats against politicians.

Arriving in Canberra, Nationals MP and former party leader David Littleproud said politicians had to learn to "play the ball, not the man".

"I think unfortunately we have crept into playing too much of the man, not just in parliament but outside of it as well," he said.

Liberal MP Ted O'Brien said the warning was a "sombre reminder" for all politicians to consider their rhetoric and behaviours.

Asked if politicians needed a code of conduct, Mr O'Brien said he would not pre-empt conversations between colleagues but said everything must be considered.

"What gives me great comfort though is that I think there is a genuine desire on the part of everybody to improve the way things are," he said.

"Parliament can sometimes be a microcosm of our community. There is a lot of anger, a lot of social discontent."

Parliament will resume its usual schedule on Tuesday, with the government hoping to pass its Digital Duty of Care, gas reservation and trust tax legislation before the end of the year.